“It has been a long day,” a delighted Geniez said afterward. “I went from the start in a group and we worked well together, everyone collaborated to obtain the maximum time gap in the breakaway. Two kilometers from the finish was when I saw that I had the victory in my legs and it was a special motivation for me to win here in France.”

Following a tough day of climbing into Andorra on Saturday, when 16 riders were forced to withdraw due to the brutal weather conditions, Sunday’s stage — the longest of the three-week race — was even more daunting, with four category-one climbs.

However, Geniez did not show any signs of fatigue, as he was part of a breakaway group of six riders that led a chasing pack of 19 by more than two minutes, and the peloton by more than seven minutes by the time they had completed the climbs over the Colle del Canto and Port de la Bonaigua.

The 25-year-old then attacked on his own with fully 25km still to go, but having maintained a significant advantage over the peloton he began the climb up the Col de Peyresourde to the finish line with still more than five minutes of an advantage and was never threatened.

However, there was still plenty to fight for in the overall race standings on the climb to the finish as all the major contenders grouped together before a series of attacks and counterattacks were launched.

Katusha’s Joaquim Rodriguez and Movistar’s Valverde were first to show their hand, but Nibali always ensured they could never get away and in the end there was no change in the top five of the general classification as those three, Horner and Italian Domenico Pozzovivo all registered the same time.

Despite maintaining his lead after another crucial stage, Astana’s Nibali is not taking anything for granted, with four more mountain stages still to come.

“I tried to go in the last climb up to Peyragudes, but it was difficult, with so many continuous attacks it was a crazy stage with a lot of movement,” the 2010 Vuelta winner said. “We will see how things will go in Formigal tomorrow after two days with such great accumulated fatigue. There are still important climbs to come like in Pena Cabarga and Angliru.”